Most of lidar systems are being manually operated on site, therefore, a frequency of observations is limited due to a manpower etc if the lidar site is geographically far away from a laboratory. In such a case, an unattended automatic lidar system or a remote controllable one is expected as for increasing the frequencies. On the other hand, as well known, a computer is linked to the other through the Internet, and remotely operated each other. We have proposed the Internet LIdar System (named ILIS) as the unattended operational lidar. A concept of the ILIS is controllable through the Internet, anytime and anywhere. The ILIS proposed here has been successfully operating every night without any difficulty of the geographical distance of 1,000km.